// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
/*
 *  LuminanceSource.cpp
 *  zxing
 *
 *  Copyright 2008 ZXing authors All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <sstream>
#include <zxing/LuminanceSource.h>
#include <zxing/InvertedLuminanceSource.h>
#include <zxing/common/IllegalArgumentException.h>

using zxing::Ref;
using zxing::LuminanceSource;

LuminanceSource::LuminanceSource(int width_, int height_) : width(width_), height(height_) { }

LuminanceSource::~LuminanceSource() { }

bool LuminanceSource::isCropSupported() const {
    return false;
}

Ref<LuminanceSource> LuminanceSource::crop(int, int, int, int) const {
    throw IllegalArgumentException("This luminance source does not support cropping.");
}

bool LuminanceSource::isRotateSupported() const {
    return false;
}

Ref<LuminanceSource> LuminanceSource::rotateCounterClockwise() const {
    throw IllegalArgumentException("This luminance source does not support rotation.");
}

LuminanceSource::operator std::string() const {
    ArrayRef<char> row;
    std::ostringstream oss;
    for (int y = 0; y < getHeight(); y++) {
        row = getRow(y, row);
        for (int x = 0; x < getWidth(); x++) {
            int luminance = row[x] & 0xFF;
            char c;
            if (luminance < 0x40) {
                c = '#';
            } else if (luminance < 0x80) {
                c = '+';
            } else if (luminance < 0xC0) {
                c = '.';
            } else {
                c = ' ';
            }
            oss << c;
        }
        oss << '\n';
    }
    return oss.str();
}

Ref<LuminanceSource> LuminanceSource::invert() const {

    // N.B.: this only works because we use counted objects with the
    // count in the object. This is _not_ how things like shared_ptr
    // work. They do not allow you to make a smart pointer from a native
    // pointer more than once. If we ever switch to (something like)
    // shared_ptr's, the luminace source is going to have keep a weak
    // pointer to itself from which it can create a strong pointer as
    // needed. And, FWIW, that has nasty semantics in the face of
    // exceptions during construction.

    return Ref<LuminanceSource>
            (new InvertedLuminanceSource(
                    Ref<LuminanceSource>(const_cast<LuminanceSource *>(this))));
}
